The present invention relates to a safety device for vehicle occupants.
From GB-PS 1,368,899 a safety device is known having a collision switch and a delay sensor as well as having a coincidence comparator connected to the collision switch and the delay sensor. The coincidence comparator receives electrical signals from the collision switch and from the delay sensor and interrupts the operation of the device if these signals do not arrive within a presettable length of time. In this way false release of the safety device is prevented.
From U.S. Pat. No 3,701,903 a piezoelectric vehicle collision sensor is further known in which two piezocrystals with sensitivity axes arranged differently in space are disposed inside a vehicle, the two piezocrystals being connected electrically in parallel in a single evaluation circuit.
In this known safety device or this known sensor it is not possible to check the acceleration-sensitive sensors for functionality continuously, i.e., in particular, also during operation of the vehicle. The disadvantage of this is, however, that high reliability of such safety devices, also with respect to failure of a sensor, cannot be ensured.